Process and machine for threading the necks of tubes



Nov. 7, 1933. E. H. BARKER 1,934,292

PROCESS AND MACHINE FOR THREADING THE NECKS OF TUBES Filed Dec. 31, 1930 6 Sheets-Sheet 1 Nov. 7, 1933. E. H. BARKER 1,934,292

PROCESS AND MACHINE FOR THREADING THE NECKS 0F TUBES Filed Dec. 31, 1930 6 Sheets-Sheet 2 Nov. 7, 1933. E H, BARKER 1,934;29'z

PROCESS AND MACHINE FOR THREADING THE NECKS OF TUBES Filed Dec. 31, 1930 Sheets-Sheet 3 E. H. BARKER 1,934,292

PROCESS AND MACHINE FOR THREADING THE NECKS OF TUBES Nov. 7, 1933.

6 Sheets-Sheet 4 Filed Dec. 51, 1930 6 Sheets-Sheet 5 E. H. BARKER Filed Dec. 31 1930 PROCESS,AND MACHINE FOR THREADING THE NECKS 0F TUBES my mm J, WW 5 Nov. 7

Nov. 7, 1933. E. H. BARKER 9 3 PROCESS AND MACHINE FOR THREADING THE NECKS OF TUBES Filed De c. 31, 1930 e Sheets-Sheet s Patented Nov. 7, 1933 PROCESS AND MACHINE FOR THREADING THE NECKS OF TUBES Edwin H. Barker, Moylan, Pa., assignor to A. H.

Wirz, Inc., Chester, Pa., a corporation of Pennsylvania Application December 31, 1930 .Serial N0. 505,892

17 Claims. (Cl. 113 44) My invention relates to forming metallic objects by pressure and particularly to threading the necks of collapsible metallic tubes in which tooth paste, shaving cream or the like may be placed.

The main purpose of my invention is to form a metallic object by pressure of a resilient solid die against-a rigid die.

A furtherpurpose is to thread the neck of a tube by.internal concurrent pressure.

A further purpose is to form threads on the neck of a tube by applying pressure to a die of rubber or the like, the -die pressing the metal of the tube into threads in a rigid die to form threads on the neck of thetube.

A further purpose is to provide mechanism by which threads can be formed on the neck of a tube by manually placing the tube on a mandrel, placing a die about the tube on the mandrel, applying pressure to, one end of the tube on the mandrel, and causing compression of a rubber die which is secured inside the mandrel and projects therefrom to form threads on the tube as a result of axial movement of a press.

A further purpose is to provide a pressure threading mechanism that is operated by a punch press or the like which comprises a mandrel for receiving a tube, and a cam-operated outer die adapted to engage and disengage the ends of the tube about the mandrel and cause pressure to be exerted against the end of the tube.

A further purpose is'to thread the neck of a tube in adie, by presenting a tube on a mandrel to a die, locking the die to the tube and the mandrel by partial vertical movement of the press head, and continuing vertical movement of the press-head applying pressure to the end of the mand'relto form threads on the tube.

A further purpose is to provide a resiliently operated mandrel which presents a .rubber extension to.the interior of the neck of a tube. A further purpose is to provide .a two-part mandrel having one'part movable and the other part stationary adapted to present a rubber sleeve to a' tube for pressure threading.

A further purpose is to provide a larger interior neck portion of a tube by resilient expansion of the tube.

volved and to mechanism by which the methods can be carried out.

Further purposes will appear in the specification and in the claims. I have preferred to illustrate one form only of my invention with a minor modification, showing My invention relates both to the methods in it in application to a press, selecting a form that is practical and eflicient in operation and which well illustrates the principles involved.

Figure 1 is a front elevation of a press with my pressure threading device in place on the press and with a tube in position for threading.

Figure 1a is an enlarged section through the dies seen in Figure 1.

Figure 2 is a vertical section taken on the line 1 22 Of Figure 1. Figure 3 is an enlarged vertical section taken on the line 33 of Figure 1.

Figure 4 is avertical section taken on the line 44 of Figure 3.

Figure 5 is a vertical section similar to Figure 4 but with the parts in a different position.

Figure 6 is a bottom plan view of the die locking device, showing in closed position means I employ, corresponding to the line 66 of Figure4.

Figure 7 is a view similar to Figure 6 but showing the locking device in open position.

Figure 8 is a fragmentary sectional elevation of a tube before the threads have been pressed on the neck thereof.

Figures 9, 10 and 11 are enlarged detail views of a portion of the structure seen in Figure 4 showing difierent steps in the formation of a thread in the neck of a tube.

Figure 12 is a sectional plan view taken on the line 12-12 of Figure 11.

Figure 13 is a fragmentary sectional elevation of a tube after the threads have been pressed thereon.

Figure 14 is a fragmentary elevation similar to a portion of Figure 1, but showing a modification of the arrangement of the structure.

Figure 15 is a vertical section taken. Q line 1515 of Figure 14. v

Figure 16 is a vertical section similar to Figure 13 showing a tool in cuttingposition at the end n the of the tube.

The tube is extruded instantaneously to include a neck or nipple having a closed discharge end.

In the past threads have been cut or rolled in a thick neck resulting in waste of metal and also requiring extreme accuracy in positioning the cu ting tool, due to the very delicate construction The present method and apparatus'offer some advantages over this threading invention, particularly in speed, and do not require the same care in accuracy of adjustment as does the patented form.

Almost all of these tubes are made of pure 1:; tin. In some cases, where the content is notcapable of contamination, lead alloys and even pure lead are used. The thin tube and neck walls are easily injured and require corresponding care in threading the neck.

I have found it very desirable to-form the neck extension of the tube with walls of somewhat greater thickness than the tube, forming the discharge end of the neck closed and initially of thickened material which is subsequently trim-- med.

. With the thin wall neck cons 1 truction I flnd that by applying pressure outwardly to the wallsof the neck against a' restraining threaded die it is possible to form a very accurate thread in the neck of .the tube.

In Figure 1 I have shown my invention as applied in a punch press} which is the simplest form I know in which .to apply it commercially with speed and which, for present purposes, I therefore view as a largely diagrammatic illustration of the invention, notwithstanding that a press of this character-has been used by me in practical operation to thread the tubes.

The vital parts of the invention are represented in relatively enlarged section in Figure 1a, in whichI show the tube 20, shoulder21, discharge nipple or neck 22 and closed end 23 inposition with the nipple unthreaded and located betweentransversely separable threaded outer dle members 24 and 25. Within the tube is a mandrel 26 which supports the top of the tube and whose tapered end 2'7 supports the shoulder of the tube against the dished faces 28 and 29 of the outer die. Within the mandrel moves a plunger 30 by whicha resilient material 31 is longitudinally compressed to cause it to expand radially against the interior of the discharge neck to swell the discharge neck outwardly into.engagement with p the interior threads of the outer die.

drel during the time that the plunger and the male die carried with it are retracted atleast \partly within the mandrel as seen'in Figure 9. This is therefore considered as the feeding position of the plunger 30 and the'male die 31 The plunger and male ,die are movable from the feeding position of Figure 9 to the positions of Figure, 10 and Figure 1 1. The pressing begins with the position in Figure 10 and continues to '65 complete the threading operation as seen in Figure 11. Either of these and any range between the two may therefore be considered as the pressing position or positions of the plunger and 'male.

die.

i170. -Because the resilient material performs die functions I have preferred to call it a die. The end of the discharge nozzle-is supported by an anvil-or stop 32.

It will be obvious that the essential parts com- -'.5 prise the outer die members, a stop t tgkethe thrust of the inner die, the inner die itselfsand means for compressing and thereby expanding the inner die, without regard to whether the in-' ner die be hollow or solid and without regard to the material of the inner die, except that it must. be capable of the function described. I For convenience of holding, and because it can be purchased to advantage in that form without necessity for special manufacture, the inner die 31 is shown in the form of a tube which can be mounted upon the serrated nose 33 of the plunger 30. It is, of course, necessary that the tube be properly mounted and supported, that the plunger be guided and that the inner die be externally supported back of its effective operating point, but these features are rather cooperative to ap-.; ply the inner die to its workthan directly eflec-' .tiveto form-the thread. My invention contemplates the use of these additional aids in applying the interior expanding die to its work. 1

Because of the requirement of the statute I have shown one mechanism for properly resiliently supporting the parts, such as are shown in Figure 1a, for example, and for pressing and guiding them to their duty. These form the parts of a punch press 34 shown in 1 and 2, and in' less detail in various other figures.

In the pressthe base plate 35 of the mandrel support 36 is'mounted upon the press bed 3'1.

The mandrel support 36 from bed 37- comprises upward extensions 38 and 39 which form bearing support for a pin 40 about which a rocker arm 41, is pivoted. Y 6' v Because resilient support for the mandrel is highly necessary I supply this by a convenient form movable on thepin to permitaccess for loading The rocker arm 41 is reduced at its upper end 42 and forms a shoulder 43 on which is .mounted a bottom spring-supporting plate 44.

An upper pin-carrying plate 45 has secured therein a number of guide pins 46 that project downwardly and through openings 47 in the lower plate 44. J

Springs 48 surround the pins 46 between the upper and lower plates 45 and 44 to allowreslli ence between the upper and lower plates.

The mandrel 26 is placed on the upper plate 45 and is free to movevertically a short distance. The mandrel is centered by a spindle 49 enlarged at 50 to fit an opening 51 in the rocker arm 41 r25 and secured thereto by a set-screw 52. V

The spindle 49 is reduced in diameter at 53 to project through an opening 54 in the upper plate 45 into an enlarged hollow portion 55, of the The tube to be threaded is'placed upon the man- 59 to .receive a threaded end 60 of the mandrel 1.3:

end 61 tapered at its outer end. 27 to conform to the shape of the breast or shoulder of a tube. The mandrel ,nd is bored at 62, and counterbored at 63, the borej62 to receive' the plunger 30 andthe counterbore 63 to: receive the enlarged head 64 of the plunger. The threading at 58 permits ready separation of the parts so that the plunger 30 carrying the male die can be removed and a new male die may be replaced upon the serrated nose 33 of the plunger. \Y

A spring 65 is placed about the reduced plunger 30, between the head 64 and a shoulder 66 formed by the end of the counterbore 63., l

The operation of the parts shown in Figure 1a ha alreedrbeeas p a ed. I

To a slide 67' which is fastened on the head 68 of the punch press I mount die clamping mechanism in the form of a base 69 which may conveniently serve as stop 32, to which are pivoted at 70 the split die members 24 and 25.

At their outer ends 71 the die members are recessed at 72 and 73. In the recessed portions a cam 74 is pivoted to a cam shaft 75, the outer surfaces 76. and 77 0f the cam 74 cooperating with the ends 71 of the die members to move them into and out of engagement with the neck of the tube. The inward movement of the die members is aided by springs 78 fastened to and between the die members.

A guide and stop pin 79 is placed on the base to assure positive registry of the die members in closed position. 7 g I The cam shaft has pivoted thereon a closing member 80 provided with gripping fingers 81 and 82 that engage the outer ends of pins 83 and 84 to clamp the dies about the neck of the tube.

An actuating lever 85 is pivoted to the cam shaft 75 and carries a roller 86' at the end of an arm 87. The roller 86 operates in a cam slot 82} in a plate fastened to any stationary part of the press to open and close the die members.

As seen in Figure 2 the mandrel and its support can be swung on its pivot against the action of a spring- 89, one end of which is fastened to the extended arm 90 of the rocker arm 41 and the opposite end of which is fastened to the bed plate of the press.

Swinging of the arm and mandrel allows the operator to place a tube upon the mandrel, after which the mandrel is allowed to move back in line with the head of the press bringing the tube .in line with the die on the head of the press.

At this point of operation, the head of the press starts to move down into the position seen in Figure 5. The clamping die assumes the position illustrated in Figure 7.

Further downward movement of the press causes the head to move down further and at the same time the arm carrying the roller is moved in the cam slot secured to the stationary structure of the press. This causes the die members to tighten about'the neck of the tube, the

locking members of the die assuming a position corresponding to that shown in Figure 6.

Final movement of the press head causes the rubber die to expand and force the thin metal of the neck of the tube into the threads formed in the die, completing the threading operation.

It will be noted that, as the press operates the resilience of the springs 48 causes the mandrel to move downwardly some distance before the rubber sleeve is exposed any considerable distance outside the end of the mandrel in position to be expanded against the tube nipple.

When the mandrel is pressed downwardly as before mentioned the'enlarged head 64 of the plunger will engage the end of the reduced portion 56 of the lower spindle 49 which will force the plunger outwardly along with the rubber carried by it.

The end or outer closing portion 89 of the tube is of somewhat thicker material than that of the side walls as explained and as seen in Figv ures 8, 9, 10 and 12, in order that its stiffening with a spiral face 91 about an open center 92. The extension 93 of the spiral face throughout a considerable part of the circumference of the hollow tool is found to be quite advantageous in preventing objectionable curling of chips cut and keeping the chips from interfering with the operation.

In Figures 14; and 15 a modification is shown in which the supporting mandrel is secured to a slide in the head of apunch press and the threading die is fastened to the bed plate.

The parts are identical to that shown in the previous figures except that the mandrel support does not swing and spring fingers 94 are used to hold the tube in place about the mandrel. Another variation in the construction is that the cam that moves the die-operating arm is carried by the movable head of the press. I have accordingly given the parts the same reference numerals.

It will be evident that my broad invention, which comprises forming metallic objects be tween a rigid die and a solid resilient die, as well as the specific application of my invention to the threading of collapsible metal tubes, is subject to numerous variations, which, however, though not as advantageous as those shown in my preferred form, wouldbe satisfactory or possibly even desirable in certain cases.

It will be evident that the tube or other object which is being formed need not be fluidtight. This has a distinct advantage over methods employing fluid pressure in forming, where fluid-tightness is essential. In Figure 17 I show the end ofthe tube open at 95. This open-end tube could be used in any of the forms of my invention, but it is less desirable than the closedend tube, because the metal closing the end likewise stiifens the end of the tube and is an extra security against distortion. -I therefore prefer to cut off the end of the tube subsequent to the threading operation, although the end of the tube could be cut off before threading as indicat- .the tube, or else the male die must be made in several separable parts. Subject to these objections, a resilient female die and rigid male die may be employed. In Figure 17 I indicate a resilient female die 96 formed in the shape of a ring, supported by a collar 97 and tightened by pressure of a tapered sleeve-like extension 98 of a plunger 99. Themale die 100 is in this case rigid, so that the tube walls may be forced by the resilient female die radially inward into the male die.

Of course the contour of the male and female dies will depend upon the shape which is to be produced and the characterof the work upon which the dies operate. My invention is not restricted to threading of collapsible metal tubes,

but is applicable to the metalshaping and stamping arts generally and may be applied to shape dreis, whether operation be upon several mandrels at one time or successively upon different mandrels and whatever the means for progressing the mandrels and for charging and discharging the work to and from the The character of char8in8,'discharging and conveying means used are matters of convenience only, relating rather to the speed of operation of e the press than to the method of forming the metal, and I of course intend my invention to be applicable in any setting, whether automatic or The addition of special attachments to the press or to the mandrel, such as, for example, blow-oil means for removing the tube from the mandrehwhether employing compressed air or otherwise, is not important to the present invention and is rather likely to complicate the draw-, ings and description and therefore has beenpmit-' ted from the illustration, but it will be under- In view of my invention and disclosure variations and modifications to meet individual whim or particular need will doubtless become evident to others skilled in the art, to obtain part or all of the benefit of my invention without copying the structure shown, and I, therefore, claim all such in so far as they' fall within the reasonable spirit and scope of my invention. 7

Having thus described my invention, what I claim as new and desire to secure by Letters.

Patent-is:

1. In a device for forming tubular metal objects, a female die, a cooperatingmale die, one.

surrounding the other, one of which dies is rigid and the other of which is a resilient solid, and

means for moving one of the dies lengthwise of the tubular objects with-respect to the other to clear the dies in one direction of movement and to insert the one die within the other and expand the resilient solid material by engagement with a flxedsurface.

2. In a device for threading the end of a collapsible metal tube, a rigid threaded female die to surround the end of the tube, a rub-' her male die adapted to lie within the endof the tube, a plunger upon which the rubber die is mounted, means for moving the plunger lengthwise of the tube to insert the male die within the tube end and to expand the male die and the tube wall 'outward against the female die, and a stop for the end of the tube. r

3. In a device for forming tubular metal obiectma support for the tubular objects, -a male die movable longitudinally therein and a split female -die therefor comprising pivoted die halves pivoted at one end each, a stop limiting the movement of the halves toward each other to their intended operating positions, spring means for drawing the dies t ether, and combined cam'means for locking the dies together with onemovementofthecam andfor opening them with an opposite movement thereof,

4. In a device for forming tubular metal objects, cooperating male and female dies, the female die comprising pivoted die members springdrawn toward each other, and. cam means for locking the die parts with one direction of movement and for separating the die parts with an opposite direction of movement.

5, In a device for threading the end of a collapsible metal tube, a rigid threaded female die divided into segments, means for separating the segments, means for moving the female die with respect to the tube to a position about the end ofthe tube while the segments are separated, means for closing the segments about the-end of the tube, means for locking the segments in closed position, a resilient solid male die cooperating with the female die and adapted to lie within the end of the tube, and means for expanding the male die and the tube wall outward against the female die. l

" 6'. In a device for threadingthe end of a collapsible metal tube, a rigid threaded female die adapted 'to surround the end of the tube, a resilient solid male die adapted to lie withinthe end of the tube, a mandrel supporting the male die and within which the male die enters when not in use, a-plunger movable, with respect to the mandrel in an opening through the mandrel, carryi th male die and axially compressing the male die in one position, and means for forcing the plunger against the male die to expand the male die and the tube wallagainst the female die.

Tl. In a device for threading the end of a collapsible tube, a rigid threaded female die adapted to surround the end of the tube, a resilient solid male die adapted to lie within the end of the tube,

a mandrel supporting the male die, a plunger movable with respect to the mandrel in an opening through the mandrel and engaging the male die, means for applying pressure to the plunger to expand the male die and the tube wall against the female die, and means permitting ready removal of the plunger from the mandrel for 'replacement of the male die.

8. In a device for threading the end of a collapsible metal tube, a rigid threaded female die adapted to surround the end of the tube, a. resilient solid male die adapted to lie within the end of the tube, a mandrel supporting the male die,

a plungermovable with respect to the mandrel in I an opening through the mandrel and engaging the male die, a spring resiliently urging the plunger away from the male die, and means for forcing the plunger toward the male die against the action of the spring to expand the male die and the tube wall against the female die.

9. In a device for threading the end of a col-' lapsible'metal tube, a rigid threaded female die, a. hollow annular resilient male die of solid material, and a plunger end extending into the hollow interior of the male-die by which the plunger and one end of the male die are rigidly attached, the plunger being movable with respect to the remainder ofthe' male die .to axially .compress the'male die and thus radially expand it against the tube wall.

10'. In a device for threading the end of a collapsible metal tube, a rigid threaded female die adapted to surround the end ofthe tube, a hollow ann'ular male die adapted to lie within the end of the tube, a plunger having an annularly ribbed end movable with respect to the end of the male die, extending within and pressing against the male die, and pressure means for forcing the plunger against the male die to expand the male die and the tube wall against the female die.

1'1. In a device for threading the end'of a col- .20 female die divided into a male die cooperating with 7 male die.

, 1,934,292 I 5 Iapsible metal 'tube, cooperating male and female moves axially of the tube, and means controlled dies, one of which is threaded and rigid and the by the pressure means for locking the female die other of which is a resilient solid, a mandrel supsegments together when pressure is applied to the porting the male die and movable from a feeding male die. position to a pressing position, and pressure 15. In a device for threading collapsible tubes, means operable when the mandrel is in pressing a female die havingv the outline of threads upon position forforcing the resilient die against the its interior surface, a male die cooperating with tube wall backed up by the rigid die. a the female die and comprising a rigid plunger and 12. In a device for threading the end of a cola'tubular terminal of solid material secured .to the lapsible metal tube, oooperatingniale and female outside of the plunger to move forward and backdies, one of which is threaded and rigid and the k ward, a. mandrel laterally supporting the male other of which is a resilient solid, a mandrel supdie, means for moving the porting the male die and movable from a feeding with respectlto the mandrel and acushion sup-- position to a pressing position, means for auto-' matically moving the mandrel from its feeding to 16. The method of threading the neck of a 001- its pressing position, and pressure means for lapsible tube, which consists in supporting the shoulder of the tube, in applying pressure to the inside of the shoulder to hold the tube, in laterally supporting the body of the tube, working machinery, a in surrounding the neck of the tube bya threaded plurality of segments, a contour to be given to the neck, in introducing the female die and confrubber into the inside of the neck and in applying sisting of a resilient solid, means for applying pressure to the rubber toradially expand the pressure to the male die, and means for locking. neck and formthreads on it. I together the segments of the female die respon'. '17. The method of threading the neck of a colsive to the means for applying pressure to the lapsible tube, which consists in suppor ing the outside of the shoulder of the tube, in applying pressure to the inside of 'the'shoulder to hold the backed up by the rigid die when the mandrel is in pressing position.

13 In collapsible tube 14. In a device for threadingthe end of a colaxially with respect to the tube, means for applytube to radially expand the rubber. and, form ing pressure to the male die, means controlled'by threads on the neck. 0 the pressure means for maintaining the segments c EDWIN H; BARKER. of the female die separated when the female die 7 

